"For someone living with dementia, that can look like snow," she says.

Maree McCabe says making design dementia friendly 'can be as simple as putting in a different coloured toilet seat'.

It's a scenario which has made it into the simulator.

"A particular pet project of Tanya's was the idea that different objects can basically appear to be the same thing," says developer Liam McGuire.

"We have a white laundry basket, we have a white toilet and we have a white basin," says Liam. "From a distance, we have a technology we can use that basically makes them appear identical - there is no possible way you can tell them apart."

"Only once you get very very close to them do they actually take their real shape," he says. "We can use tricks like these to make you really experience the things that people living with dementia actually have to live with."

James Bonner says making the simulator was challenging for the developers.

"We all come from a game design background and in game design you're usually trying to make things fun and engaging and intuitive and useful to the user - they have to be able to go through the environment without any impedance, they have to be able to use everything they see," he says.

"What we're trying to get across here is the experience of living with dementia," says James. "It's not a game, it's not fun, it's not amusing."

"We have to turn all of our experience in game design on its head basically invert everything we know, we have to make tihngs difficult instead of easy we have to make things almost painful instead of fun."

The process has also highlighted correlations between game design and the principles of dementia friendly design.

Using colour to differentiate doors, door handles, floors and walls can go a long way to helping dementia sufferers negotiate an environment.

"Very clearly colour coding things, labelling things and having a singular purpose for each object - these are things that game designers talk about, think about, we implement in games but we don't really think about the process that underlies it," says Opaque's art lead Norman Wang.

"That was an interesting process - to come from already knowing the answer and then finding out the question."